TITLE:   GCN CIRCULAR
NUMBER:  45098
SUBJECT: GRB 260706A: LCO optical upper limit
DATE:    26/07/07 09:30:30 GMT
FROM:    SVOM_group <svomgroup@bao.ac.cn>

A. Saccardi (CEA/Irfu), D. Turpin (CEA/Irfu), F. Daigne, M. Pillas (IAP), report on behalf of the SVOM mission team:

We observed the field of GRB 260706A detected by SVOM/ECLAIRs (Alaux et al., GCN 45089) and Fermi/GBM (Fermi GBM team, GCN 45088; Trigg et al., GCN 45093), with the LCO 1m telescope at Cerro Tololo Observatory equipped with the Sinistro instrument.

Our observation started on 2026-07-07 at 08:15:35 UT (about 16 hr after the trigger) and we obtained 3x200 s exposures in the SDSS r filter.

In the stacked image, we do not detect any new source within the EP/FXT error box (Liang et al., GCN 45097). We measure the following upper limit calibrated against the SkyMapper DR4 catalog, and not corrected for Galactic extinction:

r > 22.3 AB (3-sigma, mid-time 16.14 hr after the trigger).

This project is funded by the SVOM collaboration.